Electromagnetic circuit breaker



March 13, 1951 J. F. O'BRIEN ElAL 2,544,719

ELECTROMAGNETIC CIRCUIT BREAKER Filed Aug. 22, 1945 2 Sheets-Sheet 1 I /l 0: n

INVENTOR5 JOSEPH F. O'BIZIEN Y E EL 5. BOYNTON T O PNEY March 13, 1951 J. F. OBRIEN ET AL 2,544,719

ELECTROMAGNETIC CIRCUIT BREAKER Filed Aug. 22, 1945 2 Sheets-Sheet 2 INVENTORS JOSEPH F. O'BRIEN EAQL .BOYNTON 5 BY fig vii c1,

o/e/vsy l atented Mar. 13, 1951 ELECTROMAGNETIC CIRCUIT BREAKER Joseph F. OBrien, Lebanon, and Earl S. Boynton, East Orange, N. J assignors to John B. Pierce Foundation, New York, N. Y., a corporation of New York Application August 22, 1945, Serial No. 612,012

1 Claim.

This invention relates to electromagnetic circuit breakers, and the same has among its objects to provide a simple, efficient and reliable apparatus in which the several operating parts are so constructed and arranged that the same may be positively and accurately fitted within the circuit breaker enclosure or housing.

Further, said invention has for its object to provide an electric circuit breaker in which the operating parts controlling the making and breaking of the electric circuits are initially actuated by solenoid-induced action, and thereupon continued and completed by a cooperating snap spring or the like which serves to positively hold the said operating parts duly to circuit making and breaking positions.

Further, said invention has for its object to provide an electric circuit breaker in which the solenoid-induced moving parts are, for a part of their movement, actuated by snap spring means, and said snap spring means controlled by suitable cushioning means to avoid undue shock or impact being communicated to said moving parts in the course of the operation thereof.

Other objects will in part be obvious and, in part, be pointed out hereinafter.

To the attainment of the aforesaid objects and ends our invention consists in the novel features of construction and in the combination, connection and arrangement of parts hereinafter more fully described and then pointed out in the claim.

In the accompanying drawings:

Fig. 1 is a central longitudinal section, showing one form of electric circuit breaker constructed according to, and embodying our said invention;

Fig. 2 is a vertical longitudinal section on the line 2-2 of Fig. 1;

Fig. 3 is a transverse section on the line 33 of Fig. 1;

Fig. 4 is a transverse section on the line 4-4 of Fig. 1;

Fig. 5 is a transverse section on the line 5-5 of Fig. 1;

Fig. 6 is a transverse section on the line 6--6 of Fig. 1, and

Fig. 7 is a diagrammatic view of the circuit connection.

In said drawings ID designates a substantially fiat base of insulating material forming a partition having a shouldered circular central portion H to receive one end of a tubular casing portion [2, provided at its outer or free end with a cover [3. Upon the base ID are secured by screws l4, the inturned ends 15a of arcuate side wall members 15, which embrace an annular member l6 of insulating material; ll, 18 denote solenoids which are enclosed within casings or cups [3 having ends 20 provided with apertures in which are secured bearings 21 within which works a two-piece switch rod 22, 23 having interengaging screw-threaded ends. Upon the switch rod part 22 is fixed a plunger or armature 24 which is slidably guided within the flanges 25 at the edges of central openings in the spacing members 26 and flanges 21 at their outer edges enclosing the open, opposing ends of the solenoid casings 19. Between the outer side of the solenoid casing IQ of the solenoid 18 and the opposing surface of the insulating ring 16 are clamped a pair of retaining rings 28, 29. The ring 29 is provided along its inner edge with an annular recess 30 to receive the edge of a dished, circular spring 3| clamped upon the switch rod between the opposing, threaded engaging end parts 22, 23 thereof.

The solenoids l1, l8 and associated parts are maintained duly positioned within the tubular casing portion l2 by screws 32, see Fig. 2, which extend through threaded spacing sleeves or nuts 33 and engage with a bridge-piece 34 secured at its ends to the free ends of the arcuate side wall frame members l5. Upon the outer side of the bridge-piece 34 is secured a plate of insulating material 35 upon which are secured the corresponding ends of movable spring circuit-closing fingers 36, 36a, having normally closed or engaging contact points 3? at their free ends, one of which is adapted to engage with a fixed contact 38 on the plate 35 and connected to one end of a conductor 39 whose other end is connected to one terminal 1% of the solenoid 13. The other terminal 18a of said solenoid I8 is connected to the binding post 45, see Fig. 4, on the base 10. The contact finger 36 is connected by a conductor 42 to a binding post 46. See Figs. 3, 4 and '7. The COaCtlllg contact finger 36a is connected to one terminal 11b of the On coil I! by a conductor 42a, the other terminal Ila of the On coil being connected to a binding post 41. See Figs. 3, 4 and 7. The contact finger 36 when separated from its spring-contact connection with the coacting contact finger 36a makes electrical engagement with the fixed contact 38 which is connected by a conductor 39 to one terminal l8b of the Off coil i8. The other terminal 18a of the Off coil is connected to a binding post 45. See Figs. 3, 4 and 7.

The switch rod part 22 is provided at its outer the circuit. Thus, as best seen in Fig. 7, the 0911- tact armsare spring closed to close the control circuit through the On coil i! preparatory to control switch operation. When the On coil acts, the contact arms are separated, breaking the control circuit through the On coil and closing the control circuit through the Off coil i8, preparatory to control switch-operation, by

contact between the contact arm 36 and the fixed contact 58.

The other threaded end of the switch rod part 23 extends through an aperture 50 in the base It] and is secured by washers i and nuts 52, by insulating disks 51a to the intermediate portion of a resilient loop spring 53, see Figs. 1, 2 and 4 secured at its ends to a bridge member or plate 54 carrying contacts 55, 56. The spring 53 is insulated from the plate 54 by a transverse member 5'! of insulating material having its bifurcated ends guided by posts 58 secured to the base 18.

The contacts 55, 56 are adapted to engage with fixed contacts 59, 60, respectively, secured to the inner ends of straps 61, 62 on to the partion i9 and connected at their outer ends to binding posts 63, 64, respectively, included in the main circuit l4, 75.

The circuit closing contact members and associated parts are enclosed by a relatively short tubular casing portion 66 and closure 57 secured to the end of said casing partition 66 by screws 68 engaging the threaded outer ends of the spacing members or posts 58 on said partition l0, and the entire device may be securedto any desired support by a bracket 69 having oiiset ends through which extend screws Ti and into a wall or fixed support 12.

The main circuit conductors i4, 75 are are connected to the terminals 63, 64, respectively, and the circuit is controlled by the closing device which includes the elements 55, 56 and 59,66, under the influence of the solenoid means i1, i8 and the snap-spring disk 3 1.

When the solenoid coil H is energized through the leads Ila, 11b, 92a, contacts 36a, 37, 36 and lead 42, the switch rod parts 22 and 23 will be moved to the left, as shown in Fig. 2, and cause the end 4'! of the switch rod part 22 to separate the contacts 36, 36a, and simultaneously move the contacts 55, 56 on the bridge member 54 into engagement with the contacts 59, 69 to complete the main circuit. As the armature parts 22, 24 move to the left, as viewed in Figs. 1 and 2, the movement thereof will be aided by the snapspring 3|, until the dead center is overcome, whereupon the switch rod will be held positively locked by the action of said snap-spring disk 3!. When the main circuit including the contacts 55,

the switch rod parts 22, 23 to move to the right, as shown in Fig. 2, and overcome the tension of the snap-spring disk 31 and thereby withdrawing the end 41 of the armature of its engagement with the contact fingers 36, 36a, and cause the said switch rod parts 22, 23 to move to the right, and the contacts 55, 56 to become disengaged from their cooperating contacts: 59, 66, and thus break the main circuit 14,75.

Whereas, we have illustrated and described our invention by reference to typical preferred embodiments of the invention, it will be understood that changes and modifications of the invention may be made without departing from the inventionas'defined by the appended claim.

An electrical circuit breaker comprising 9, casing; a set of contacts respectively connected in a load circuit; On and Oif coils stationarily mounted in said casing; an armature in electromagnetic relation with said coils; means including'a sw'itch'rod for reciprocally mounting said armature; and cont'acts'carried by said switch rod for engagementwith said load circuit contacts upon excitation of said On coil; in combination with a pair of electrical contact arms spring closed to close the circuit connections with said On coil; means carried by said switch rod for separating said pairof contact arms to break the circuitthrough'said On coil; and a contact engageable by one of said contact arms when said 56 and 59, 60 is to be broken, the solenoid coil 18 is energized through leads 18a, 18b, 39, contact 38, lead 42 and terminal 46, and thereby cause contact arms are separated for closing the circuit through said Off coil; whereby excitation of said On coil moves said armature and said switch rod to close the load circuit, to break the circuit' through'said .On coil, and to close the control circuit through-said O-fi coil preparatory to control switch operation; and whereby excitation of said Off coil moves said armature and said switch rod to break the circuit through said Off coil and to release said contact arms for spring closing to close the circuit through said On coil preparatory to control switch operation.

" JOSEPH F. OBRIEN.

E. S. BOYNTON.

REFERENCES CITED I The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 815,826 Hill Mar. 20, 1906 1,337,469 Platt Aug. 20, 1920 1,571,401 Erickson Feb. 2, 1926 1,883,766 Cox 'et'al Oct. 18, 1932 1,918,798 Churcher July 18, 1933 2,000,136 Huss May 7, 1935 2,279,395 Gardiner Apr. 14, 1942 2,289,086 Van Valkenburg July 7, 1942 2,335,888 Stilwell Dec. 7, 1943 2,358,357 Stilwell 1 Sept. 19, 1944 2,417,438 OBrienet a1. Mar. 18, 1947 FOREIGN PATENTS Number Country Date 609,420 Germany Feb. 14, 1985 818,454 France June 21, 1937 

